JUNE
2000

 

 

 

By
Tom Turpin
 
Professor of
Entomology
Purdue University

 

 

 

 

 

06-08-00

Pollen-Packing Mamas of the Insect World

Pollination is the process by which most plants reproduce. Pollination results in seeds that germinate into new plants.

It is not a surprise to most people that pollen is a key ingredient in the pollination process. Pollen is the package that moves between parts of the plant or between plants for the purpose of fertilization.

Sometimes plants are self-pollinating. Other times the wind carries the pollen from plant to plant. Still other plants depend on insects to transport the pollen. These plants generally have showy flowers to attract the potential pollen-packers.

Some insects that carry pollen are especially well equipped for the task. Most are covered with a heavy coat of hairs. Insects, like the bumble bees, are fuzzy in appearance. The hairs on these insects have a large number of hooks and teeth. When the insect goes into the flower, either looking for pollen or nectar, the hairs become covered with pollen.

What happens after the pollen-covered insect emerges from the flower is a fascinating process. It is a grooming miracle, using brush and comb, all while the insect is in flight. 

On the foot of the hind legs of bees are pollen brushes. So while the bee flies to the next flower, it uses the brushes on its hind legs to brush its hairy body. In the process, the pollen is removed from the hair and collects in the brush.

The grooming bee then removes the pollen from the brush by using a comb that is on the lower end of its leg. This, of course, requires that both legs come into play. The comb from the left leg removes the pollen from the right leg and vice versa.

Once the pollen is in the comb of the leg, it is packed into what is called the pollen basket. This basket is just a hollow spot, ringed by two rows of spines on the inside of the back leg.

The middle legs of the bee are used to pack the pollen into the basket. The bee sometimes adds a little honey to the pollen to help produce the solid mass that the bee will carry back to the hive. Once in the hive, the pollen packets are removed from the legs of the field bee and placed into the pollen cells in the comb. There, it is packed into the cells by hive bees where it will remain until it is needed as food.

Not all bees collect pollen with their legs. Some bees have an abdominal brush. In these bees, such as the leaf-cutter bees, the pollen is carried to the nest in the brush. There, it is dusted off so that it can be concentrated for storage.

Other pollen-carrying bees just swallow the pollen that is collected on their bodies. It is carried to the nest in the crop along with the nectar. When these bees get home, they just spit out the gut contents and it is stored for later use.

Humans have come to recognize that pollen might have benefits for their health. Some of us who suffer from hay fever, due to air-borne pollen, might beg to differ, though. Nonetheless, there is a market for pollen.

Some beekeepers put pollen traps on their bee hives. As the field bees carrying pollen enter the hive, the trap causes the pollen packets to drop from the bees. The beekeeper then collects the pollen so that it can be packaged and sold at health food stores.

So maybe the sales slogan for the pollen might be something like this: Brushed and combed from the hairs of knees of pollen-packing mama bees!

 

Writer: Tom Turpin
Editor: Olivia Maddox